Rock-drilling machine.



W. S. BENJAMIN.

ROCK DRILLING MACHINE.

APPLICATION FILED JUNE 17, 1912.

1,087,632. Patented Feb. 17, 1914.

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ll/W/i'amci 56/7 'am/fa WILLIAM S. BENJAMIN, 01E SEATTLE, WASHINGTON.

ROCK-DRILLING MACHINE.

Specification of Letters Patent.

Patented Feb. 17, 1914.

Application filed June 17, 1912. Serial No. 704,048.

To all whom it may concern Be it known that I, WILLIAM S. BENJA- MIN, acitizen of the United States, residing at Seattle, in the county of Kingand State of \Vashington, have invented certain new and usefulImprovements in Rock-Drilling Machines, of which the following is aspecification. V

This invention relates to improvements in rock drilling machines, and isintended more especially for submarine Work, although it mayadvantageously be used in other situations.

The object of the invention is to provide an efiicient machine of thischaracter which will be of simple construction, easy to operate, and notliable to become deranged when subjected to rough usage.

The invention consists in certain structural features and combinationsthereof, substantially as hereinafter described and claimed.

In the accompanying drawings, Figure 1 is a longitudinal verticalsection of an embodiment of the present invention. Fig. 2 is a view ofthe same shown partly in elevation and partly in section.

In carrying out my invention, I provide a bored barrel which, forconvenience of manufacture, is desirably composed of two parts 1 and 2rigidly connected together. Extending into the bore 3 of the lowerbarrel part 2 is a reciprocating percussive memher 4, and a heavy piston5, or hammer as it will hereinafter be called, within the other part 1.Detachably secured, as by pins 6, to the lower end of the percussivemember is a head 7 which is rovided at its center with a socket 8 for arill-bit 9 of a length to extend from a distance below said head up intoa recess 10 provided in the adjacent end of said member. The drill-bit 9is desirably made of a single piece and is formed with a plurality ofradially disposed blades 9 at its lower end and above such blades thebit is provided with an axially disposed passage 9 which communicateswith the various angular spaces afforded between said bit blades. Thehead 7 has in its under side a number of grooves 11 arranged radially orapproximately so, to the axis of the head. Removably seated within thesehead-grooves are cutter elements 12 which are each secured in itsrespective grooves in any suitable manner as by a key 13.

15 represents a cover plate for the barrel part 1 and extending axiallythrough this plate, the piston 5 and the member 4 is a pipe 16 whichextends from the bit 9 to an elevatlon in proximity to the surface ofthe water in which the machine is operating. Packing rings 17 and 17 areprovided between the .inner and outer peripheral walls of member 4 andhammer 5 to prevent leakage of the actuating fluid between these partsand the pipe and barrel walls.

Rigidly connected to the barrel or to the cover plate 15 thereof is acylinder 18 which is divided by a partition 19 into an upper chamber 20and avalve chamber 21 therebelow.

I 22 represents a pipe for the motive fluid, preferably compressed air,supplied to the upper end of chamber 21, from an air compressorpositioned upon a float or vessel (not shown) which likewise carrieshoisting apparatus for controlling the lines 23 Whereby the machine issuspended while being lowered to the surface of the rock to be drilled.After being so lowered suflicient tension is maintained on the lines toretain the machine in upright position until at least it has entered therock sufi'iciently to be held upright by the drilled hole. Adjacent tothe lower end of the valve chamber 21 is a port 24 which is connected bya passage 24 with the bore of the barrel at or about the plane of theupper end of the member 4 when the same is in its uppermost positionwith respect to the barrel. Intermediate the openings of said supplypipe and the passage 24 into the valve chamber, the latter is providedwith an exhaust port 25 which leads into a pipe 25' which dischargesinto the pipe 16 and serves as an ejector element whereby the column ofwater within the pipe 16 is induced to ascend by the discharges from thepipe 25 and whereby the comminuted rock, as broken away by the drill bit9 and cutter elements, are carried upwardly with the water anddischarged from the upper end of the pipe 16.

In order to prevent the water from flowing through pipe 25 into thevalve chamber, I provide a non-return valve inthis pipe positionedwithin a nozzle end 25 of the pipe. In proximity to the upper end of thevalve chamber 21 is a port 27 which communicates by a passage 27 and aport 27 with the barrel-bore at a short distance below the cover plate15 of saline. At a extends to an opening 28 near the conclusion of theother stroke,

r Fig. 1. As,

higher elevation than the port 24: ofpassage 24! is a port 28 of apassage 28' which the upper end of the chamber 20. Fitted forreciprocation within this chamber is a piston 29 which is connected by astem 30 extending through a packing box provided in the partition 19with a slide valve 31 provided in the chamber 21'. 'Interposed betweenthe piston 29 and said partition is a helical spring 32 which tends tourge the piston and the slide valve upwardly to occupy the positions inwhich they are represented in I illustrated, said slide valve consistsof a c lindrical body of a length approximating the distance between theport 22' of the air supply pipe 22 and the port 24 of the passage 24'which communicates with the barrel-bore. The valve is characterized byhaving a by-pass 31' extending through its entire length and by beingprovided with a peripheral recess 31 of suflicient length to connect theports 24 and 25 of the respective passages when the valve is at thelower end of its travel as shown in Fig; 2.

4: represents a collar formedon or rigidly secured to said percussivemember and is operable within a counter-bore 3 of the barrel to limitthe strokes of the percussive member by encountering an end of suchcounter-bore at the termination of one stroke and being, upon occasion,arrested at by an elastic bumper-ring 33 which is supported by anannulus 35 secured to the under side of the barrel as indicated inFig. 1. The bumper ring- 33 is, however, brought into play only when themachine is actuated while away from the work and is designed to preventany undue impact being then delivered to the machine structure. I I

An exhaust pipe 36 leads from the upper end of the chamber 20 to themain exhaust pipe 25'. Included in the pipe 36 is an adjustable valve.36' whereby the discharge opening through this pipe may be regulated toa relatively small size and through which the air which may be presentwithin the chamber will flow sluggishly therefrom and consequently actas a cushion to retard the upward movements of the piston 29 inopposition to the power exercised by the spring 30.

The operation of the afore described portion of the invention is asfollows: Assuming the various parts are in the positions in which theyare represented in Fig. 1, compressed air is supplied through pipe 22 tothe upper end of the chamber 21 whence it flows through the by-pass 31of valve31 to the underside of the latter and thence is led by passage24' to the underside of the hammer 5 to eifect the raising of the same.As hammer 5 moves upwardly the port 28 is exposed and the actuatingfluid escapes by way of passage 28 into the upper end of previouslyadmitted mamas chamber 20, resulting in the building up of a fluidpressure above piston29 which will overcome the power of spring 30 andcause the piston to descend accompanied by the valve 31 into theposition which they occupy in Fig. 2. During the ultimate portion of thedowlistroke of the valve, however, the port 27 has been closed withrespect to the flow of air from the upper end of barrel-port 1 to theexhaust pipe 25; 'The residual air within the barrel and above thehammer is compressed by the further upward travel of the hammer andafiords a cushion to gradually arrest the motion ofv the hammer andfinally reacting, and supplemented by the weight of the hammer, thelatter is forced down below the .port 27 whereupon and by ing nowuncovered by valve 31 air under pressure is delivered through passage 27to the space above the hammer to accelerate the speed of the hammer andthereby impel reason of the port 27 be it with relatively high velocityand power against the percussive member 4 which, in turn, strikes, so tospeak, the bottom of the hole being bored.' As the hammer descends theair therebelow will obviously escape through the passage 24 about theperipheral recess 31 of the valve see Fig. 2) and into exhaust pipe 25.During the downward, or striking, movement of the hammer the air to theupper end of chamber 20,escapes through the pipe 36 whereupon the spring32' asserts its-power to elevate the piston 29 and thus restore thevalve 31 to the position which it occupied at the beginning of the abovedescribed cycle of operation.

In the operation of this machine, the weight thereof bears against thework, and when the hammer 5. strikes the percussive member 4 the latteris first driven down followed by the barrel and the parts connectedthereto and delivering a second blow to the percussive member throughthe medium of the collar 4'. recoil of the percussive member 1spractically eliminated and the drilling of a hole with a machine isrendered much more rapid, as not only the momentum of said member isutilized but the weight of the entire machine is applied therewith orsupplemented thereto.

What I claim, is

1. In a drilling machine, the combination of a barrel, a piston hammerand a percussive member in the barrel, a collar provided on said memberand engageabl'e bythe barrel and means provided on the barrel andengageable by said collar for limiting the forward stroke of saidmember, a valve chamber, passages connecting the interior of the barrelwith the valve chamber, inlet and outlet openings for said chamber, a

valve in said chamber for controlling said with a barrel, a

assa es and o enin s, a s rin o eratively sonnefited vith the va ilvefdi'yitfidi gly holding said valve in position to afl'ord a supply ofthe motive fluid to said barrel to effeet the elevation of thepiston-hammer, and means controlled by the latter when it approaches theupper end of its reverse stroke whereb the motive fluid is applied tothe piston hammer to effect the forward stroke of the same.

2. In a drilling machine, the combination piston hammer arranged forreciprocatory movements therein and a percussive member extending intosaid barrel a cylinder secured to said barrel and divided into twochambers, passages connecting the lower of said chambers with theinterior of the barrel, openings provided for the supply and exhaust ofthe motive fluid to and from said lower chamber, a valve in the lowerchamber, a piston in the upper of said chambers, a stem operativelyconnecting the valve with said piston, a spring acting to elevate saidpiston and valve, a passage connecting the interior of the barrel withthe upper chamber and above the piston therein, and a valve controlledexhaust passage leading from the upper end of said upper chamber,substantially as and for the purposes described.

3. In a drilling machine, the combination with a barrel, a reclprocatorymovements thereln, and a perpiston hammer arranged for cussive memberextending into said barrel, a cylinder secured to said barrel anddivided into two chambers, a passage from a point adjacent the bottom ofsaid lower chamber to a bottom from a point removed from the top of saidlower chamber to a point slightly removed from the top of said lowerchamber, ports provided for the su ply and exhaust of the motive fluidto and .om said lower chamber positioned adjacent the top and the middlepoints thereof respectively, a valve in the lower chamber having aby-pass therethrough and a peripheral recess therearound, a piston inthe upper one of said chambers, a stem operatively connecting the valvewith said piston, a spring acting to elevate said piston and valve, apassage connecting the interior of the barrel with the upper chamber andabove the piston therein, a valve-controlled exhaust passage leadingfrom the upper end of said upper chamber.

Signed at Seattle, Washington, this 6th day of June, 1912.

WILLIAM S. BENJAMIN.

Witnesses:

PIERRE BARNES, J. V. Woonwann.

point in said barrel, a passage

